Device for administering anesthetics



Dec. '27, 1938; G. KING 2,141,793

DEVICE FOR ADMINISTERING ANESTHETICS Filed Feb. 2, 1955 2 Sheets-Sheet l Dec. 27, 1938. G K 2,141,793

DEVICE FOR ADMINISTERING ANESTHETICS Filed Feb. 2, 1955 ZSheets-Sheet 2 Patented Dec. 27, 1938 UNITED STATES PATENT OFFICE DEVICE FOR ADRIINISTERING ANESTHETICS Application February 2, 1935, Serial No. 4,684

2 Claims.

This invention relates to a device useful in inducing anesthesia and relates more particular- 13 to an apparatus for administering ether and other anesthetics. A general object of the pres- .3; ent invention is to provide a device for administering anesthetics that is in the form of a single, compact seli-contained unit that is easy and convenient to use and that is effective in inducing anesthesia with a minimum of discomfort and 10 ill eiiects to the patient.

This application is filed as a continuation in part of my application Serial No. 741,250, filed August 24, 1934.

The devices that have been introduced for U administering anesthetics may be grouped in three general classes as follows:

Class 1.Devices devoid of means for heating the anesthetic or anesthesiant mixture.

Class 2.Devic es embodying electrical means 20 for heating the anesthetic or the anesthesiant mixture; and

Class 3.Devices having a water jacket or other heating means at a point remote from the applicator or patients mask for heating the anesthetic as it flows through a tube or tubes to the mask.

The devices falling in Class 1, above noted, are

not altogether satisfactory as it has been found that heat is necessary for the proper complete 30 volatilization of the anesthetic and for the proper admixture of the anesthetic with the air and the use of devices of this class usually produces nausea and other ill effects in the patient. The devices included in Class 2 are extremely dangerous to use because the anesthetics employed are often very inflammable and sometimes explosive and a slight defect in the electric heating equipment may produce a spark suflicient to ignite the anesthetic or mixture. For this reason devices embodying electrical heatingmeans are usually barred from operating rooms. The devices falling in the above mentioned Class 3 have not proven satisfactory due to the remoteness of the heating means from the point of administration of the anesthetic. The anesthetic in its passage from the heating means loses its heat and where a volatile normally liquid anesthetic such as ether is employed it condenses or returns to its normal state before reaching the patient,'

D and the purpose of the heating means is defeated.

Another object of this invention is to provide a device for administering anesthetics that comprises a compact unit that may be applied directly over the oral and nasal cavities of the patient and that involves an improved means for heating the controllable mixtureof the anesthetic and air in the mixing chamber and the breathing chamber to maintain the proper temperature conditions throughout the various phases of the ad- 5 ministration of the anesthetic and without danger of igniting the anesthetic. The device of the present invention, providing for the proper heating of the anesthesiant mixture in the mixing chamber and the immediately adjacent breathing chamber without danger of igniting the anesthesiant mixture, completely overcomes the undesirable features inherent in the devices of the prior art.

Another object of my invention is to provide a device for administering anesthetics that is operable to deliver a proper mixture of vaporized anesthetic, air and exhaled carbon dioxide at the proper temperatures while resting on the face of the patient, and that is capable of easy accurate regulation to control the character of the anesthesiant mixture by governing the admission of air to the mixing chamber, governing the rate of discharge of the anesthetic to the mixing chamber and by regulating the exhaust valve. The device of the invention may be easily adjusted and regulated to produce or deliver a correct uniform anesthesiant mixture so that the patient does not inhale raw or unvaporized anesthetic or an excessively strong anesthetic mixture and, therefore, is less subject to nausea, headache, post narcotic pneumonia, coryza, bronchial irritation or excessive variations in the blood pressure.

Another object of my invention is to provide an anesthetic administering device of the character mentioned that embodies a simple, novel thermal insulating jacket that maintains the proper temperatures throughout the various phases of the administration of the anesthetic and that allows the device to be readily handled at all times.

Another object of the invention is to provide a I device of the character mentioned in which the mixing chamber has an inspection Window and internal reflecting surfaces whereby the rate of discharge of the anesthetic may be readily observed.

Another object of the invention is to provide a device of the character mentioned that may be easily and quickly dismantled for cleaning and sterilizing.

Another object of my invention is to provide a device of the character mentioned that does not include any projecting handles, pipes, wires or the like to interfere with its use.

Another object of the invention is to provide a device of the character mentioned that does not require great skill or experience on the part of the person administering the anesthetic.

Another object of the invention is to provide a device of the character mentioned that requires the use of a minimum amount of ether or anesthetic and permits little or no anesthetic to escape into the room.

Another object of the invention is to provide a device for administering anesthetics that is light in weight and simple and inexpensive of manufacture.

The various objects and features of my invention will be fully understood from the following detailed description of a typical form and application of the invention, throughout which description reference is made to the accompanying drawings, in which:

Fig. l is a front elevation of the improved anesthetic administering device provided by this invention. Fig. 2 is a transverse detailed sectional view taken as indicated by line 2-2 on Fig. 1. Fig. 3 is a fragmentary transverse detailed sectional view taken substantially as indicated by line 3-3 on Fig. 1 and Fig. 4 is a vertical detailed sectional view taken substantially as indicated by line 4-4 on Fig. 1 showing a portion of the reservoir and other parts in elevation.

The anesthetic administering device of this invention includes, generally, a hollow body partitioned to have a reservoir ill for the liquid anesthetic, a mixing chamber H, a breathing chamber l2, a heating jacket 13 and an insulating jacket M, a valve 15 for governing the admission of anesthetic to the mixing chamber H, valve means iant mixture from the chamber H to the chamber l2, an exhaust valve I! for the breathing chamber l2 and various other parts the details and functions of which will be hereinafter described.

The body of the device is intended to be arranged on the face of the patient so that the chamber l2 has direct communication with the breathing organs. For this reason the body is preferably compact and light in weight. In accordance with the broader aspects of the invention the body of the device may be varied considerably in construction. The reservoir H) for containing the liquid stitutes the upper portion of the body. In the particular form of the invention illustrated the reservoir 10 is cylindrical and normally has a substantially vertical longitudinal axis. An inlet or filling extension I8 is provided on the top of the reservoir i0 and is normally closed by a perforated or valved cap I9. The cap 19 may be pivotally mounted or supported as at 20. An inspection window 2| of glass or other transparent material is provided in the wall of the reservoir Hlwhereby the level of the anesthetic in the reservoir may be determined. The sight opening or window 2! is preferably provided in the front or forward side of the reservoir.

The mixing chamber l I is located below the reservoir l0 and is formed or defined by a substantially cylindrical side wall 22 and a top 23. The lower end of the mixing chamber II is closed by the valve means H5. The top wall 23 of the mix ing chamber ll is spaced below the bottom 24 of the reservoir Ill to leave or provide an insulating space 25 at the lower end of the reservoir. The top wall 23 projects laterally or radially beyond the side wall 22 to form the top walls of the i6 governing the passage of the anesthes anesthetic preferably con-' ber I2 may be heated to complete the volatilizaheating jacket i3 and the insulating jacket H. An inspection opening 26 is provided in the forward side of the wall 22 and is closed by a plate 2'! of glass or other transparent material. The interior of'the mixing chamber H is readily visi- 5 ble through the inspection opening 26. The interior surface of the wall 22 is polished or plated with light reflecting material so that the rate of discharge from the valve I5 may be more readily observed. 10

An air inlet opening 28 is provided in the wall of the mixing chamber II. The air inlet opening 28 is preferably provided in the side wall 22 above the inspection window 26 to be remote from the valve means "3. However, the air inlet opening 15 may be otherwise located if desired. A valve 29 governs or controls the passage of air through the inlet opening 28. The valve 29 is a plate-like member carried by a pivotal or rotatable shaft 36'. The shaft 30 is rotatable in openings 3| in 20 parts of the body and has a knob 32 on a projecting end to facilitate its manipulation. A spring 33 is arranged under compression between the knob 32 and a plate 3 3 to frictionally resist movement of the shaft 30 and to maintain the 25 valve 29 in its set or adjusted position. The valve 29 may be turned between a position where it substantially obstructs the opening 28 and a horizontal or fully open transverse position where it permits the free flow of air through the open- 30 ing 28. The valve 29 is preferably proportioned so that it does not completely close the opening 28 when in its upright or closed position. It is believed that it will be apparent how the valve 26 may be readily adjusted to any desired posi- 5 tion to provide for the desired rate of admission of air to the mixin chamber H.

The breathing compartment or chamber i2 is located immediately below the mixing chamber H and occupies the lower portion of the body. 4 The chamber I2 receives the anesthetic mixture or vaporized liquid anesthetic and air and is formed and arranged to directly communicate with the breathing organs of the patient. In the preferred construction the breathing chamber I2 45 is substantially oval in transverse cross section. The compartment or chamber 12 is formed or defined by a wall 35 which is downwardly and outwardly flared throughout its major portions whereby the chamber I2 is of downwardly increasing cross section. A cushion or flexible member 36 is provided on the lower edge or end of the wall 35 to engage the face of the patient. In practice the cushion member 36 may be tubular so that it may be inflated to more readily 55 conform to and seal with the patients face. A normally. closed tubular stem 37 communicates with the tubular cushion member 36 to facilitate its ready inflation. Spaced flanges 38 are provide-d on the member 36 to engage and grip the 6 opposite. side surfaces of the wall 35 to secure the member to the wall. The chamber 12 is shaped and proportioned to fully cover the oral and. nasal cavities so that the patient breathes from and into the chamber l2.

An important feature of the present invention is the provision of the heating jacket 13 whereby the mixing chamber l l and the breathing chamtion of the anesthetic and to facilitate the proper 7 admixture of heated air, vaporized anesthetic and carbon dioxide throughout the different stages of the anesthesia, whereby the patient suffers from a minimum of discomfiture and ill effects. The heating jacket substantially sur- 7 rounds the main wall or side wall 22 of the mixing chamber II and extends around a portion of the wall 35 defining'the chamber I2. The jacket !3 includes a lower forward wall portion 40 extending around the forward part of the wall 35 and continuing upwardly to surround the lower forward portion of the wall 22 of the mixing chamber. The lower end of the wall portion 45 may be joined with the wall 35 and the upper part 45 of the wall portion 40 may be turned inwardly to join the wall 22 adjacent the lower end of the inspection opening 26. The heating jacket I 3 includes an upper wall portion 4I extending around the rear side parts of the mixing chamber wall 22. The wall portion 4I joins or is a continuation of the wall portion 40 and its forward edge parts areturned inwardly to join the mixing chamber wall 22 adjacent the opposite sides of the inspection opening 26. The upper end of the space S formed by the jacket wall 4| is'closed by the top wall 23 of the mixing chamber.

The space S is of substantial volume or capacity to contain suficient heated liquid to maintain the desired temperatures in the mixing chamber II and the breathing compartment I2. A filling extension or pipe 42 communicates with the space adjacent its upper end to facilitate a the filling of the heating medium into the space.

The filling pipe 42 preferably projects from the rear part of the wall portion 4i and is provided with a suitable closure means. In the case illustrated the filling pipe 42 is externally screw threaded to receive an internally threaded cap 43. The cap 43 is provided with handles or wings 44 and carries a rotatable ring 45. A chain 45 is connected with the ring 45 to secure the cap 43 to the body of the device to prevent its loss or displacement. When the device is arranged in a substantially horizontal position the liquid heating medium may be readily poured into the space S through the filling pipe 42. The cap 43 is adapted to efiectively close and seal the outer end of the filling pipe 42.

The insulating jacket I4 encases or is provided on the heating jacket I3 to retain the heat of the heating medium contained in the space S and to permit the ready handling of the device when the jacket I3 contains a hot liquid. The insulating jacket I4 is formed by a wall or walls 4? suitably spaced outwardly from the wall portions 40, 45 and 4! of the heating jacket I3. In practice it is preferred to provide a suitable ther-' mal insulating material M in the space formed by the insulating jacket I4. However, the jacket I 4 may form or enclose an air space to constitute an insulating means for the heating jacket I3. Where insulating material M is employed it is preferred to use a material that is very light in weight such as fullers earth or cork. The insulating jacket I4 constitutes the outer wall of the major intermediate portion of the device and is preferably substantially flush with the lower portion of the reservoir It.

It is preferred to mount or arrange the reser voir It so that it may be removed for filling, etc. and so that it may be readily turned or rotated to various positions to permit the device to be arranged in accordance with various positions of the patient without danger of spilling the liquid anesthetic from the cap I9. In the particular construction illustrated in the drawings an annu- 1ar extension or flange 48 is provided at the upper end of the insulating jacket wall 4'I' to receive the lower end portion of the reservoir I ll.

The flange 48 snugly receives the lower portion of the reservoir III but the contact of the fiange with the reservoir is such that the reservoir may be turned to various positions and may be removed when desired.

The valve I 5 for controlling the admission of the liquid anesthetic to the mixing chamber II is such that the rate of discharge of the anes thetic into the mixing chamber may be very accurately controlled. The valve I 5 includes a tube 56 attached to and projecting downwardly from the bottom 24 of the reservoir I0. The tube 55 projects a substantial distance into the mixing chamber II and its upper end is open to the interior of the reservoir III. A tubular extension or flange 5I projects downwardly from the bottom 24 of the reservoir around the tube 58 and fits into an opening 52 in the wall 23. The fit of the flange 5I in the opening 52 aids in rotatably and removably retaining the reservoir I B in its proper position. The lower end portion of the tube 56 is reduced or restricted to have a small discharge orifice 53. A valve stem 54 extends longitudinally through the tube 55 and continues upwardly through the reservoir Ill. The lower end portion of the stem 54 is tapered to comprise a needle valve for governing or controlling the discharge of anesthetic from the orifice 53. The upper portion of the stem 54 is threaded through a boss 55 on the top of the reservoir ID and its projecting upper end portion has a suitable operating knob 55. A spring 51 is arranged under compression between the. knob 56 and the boss 55 to yieldingly resist turning of the stem 54 and to maintain the valve stem 54 in its set or adjusted position. The knob 56 may be engaged and turned to thread or adjust the valve stem 54 to different longitudinal positions to provide for the desired rate of discharge of the anesthetic from the orifice 53. The rate of discharge or dropping of the anesthetic liquid into the mixing chamber II may be easily observed through the inspection opening 26.

The valve means I6 for controlling the passage of anesthesiant mixture from the mixing chamber H to the chamber I2 comprises an'auto-matic check valve 59 that opens when the patient inhales and that automatically closes when the patient exhales into the chamber I2. In accordance with the invention the valve means I6 also includes an absorbent element 66 associated with or surrounding the valve 59 for absorbing liquid anesthetic that reaches the lower portion of the chamber II in a liquid state, and a splash plate 5% for receiving the liquid anesthetic dropping from the orifice 53 to break up the anesthetic into small droplets or spray. The valve 59, the absorbent element 65 and the splash plate M are associated together in a readily removable unit or assembly.

The valve means I6 includes a disc or plate 52 having an upturned annular flange 63 at its periphery for fitting the lower end portion of the mixing chamber II. The plate 62 forms a partition between the chambers I I and I 2. Releasable connecting means is provided for detachably holding the plate 52 in position. The flange 63 is provided with spaced bayonet slots 54 adapted to receive inwardly projecting pins 65 on the wall 22. The cooperation of the pins 65 with the bayonet slots 64 removably retains and supports the plate 62 in position. A suitable handle 5 is provided on the lower side of the plate 62 to facilitate its easy attachment and removal. A

series or multiplicity of openings 66 is provided in the central portion of the plate 62. The valve 59 is in the nature of a disc adapted to seat upwardly against the lower side of the plate 62 .to

close the openings 56. A stem Bl projects upwardly from the top of the valve 59 and is slidably guided by a tube 88 carried by the plate 62. The valve stem 81 projects beyond the upper end of the tube 58 and has a head or washer 59 on its projecting upper end. A helical spring 10 is arranged under compression between the washer 69 and the plate 62 to normally urge the valve 59 to its closed position. The valve ill is such that during operation or use of the device the reduced pressure created in the chamber l2 when the patient inhales causes the valve 59 to be opened against the action of the spring and when the patient exhales the spring automatically returns the valve to its closed position where it closes off the openings 65.

The absorbent element 69 is a tubular or annular body of liquid absorbing material arranged on the upper side of the plate 52 in the mixing chamber H to surround the upper ends of the openings 65. In practice the element 69 may be a body of gauze or sponge. The absorbent element 5 is retained in place by a tubular part II projecting upwardly from the plate 62. The flange B3 aids in retaining the element 60 in position. The tubular part Tl projects upwardly through the opening of the tubular absorbent .element 60. A plurality of perforations i2 is provided in the tubular part H to permit vapor from the liquid anesthetic in the absorbent element 6%! to be drawn through the openings 66 when the valve 59 is open.

The drip plate or splash plate El is located between the orifice 53 of the valve l5 and the openings 66 of the valve means l6. The splash plate iii is preferably a disc shaped member having a convexed upper surface. In practice the splash plate 6i may be supported by spaced legs 13 projecting upwardly from the plate 62. The splash plate BI is positioned so that the liquid anesthetic discharged from the orifice 53 strikes its upper side. The liquid anesthetic drips on the splash plate El and is broken into small drops to readily vaporize. The anesthetic that remains in a liquid state may run or drip from the peripheral edge of the splash plate Bl. The absorbent element 63 is proportioned and positioned to receive this liquid anesthetic that may fall from the edge of the splash plate Bl. The splash plate 6i is prer'erably'tilted or inclined-to 'face the inspection opening 26 and its upper surface is polished or plated with light reflecting material so that the rate of dropping of the anesthetic from the orifice 53 may be more readily observed through the inspection opening 26. The bayonet slots 64 and the pins 65 are related so that the plate 62 may be readily engaged in its proper position to have the splash plate tilted or inclined in the proper manner.

The exhaust valve i1 is provided to control the escape of the exhaled air and carbon dioxide from the applicator compartment or breathing chamber l2. The valve i1 is in the nature of an adjustable check valve that may be readily regulated to govern the discharge from the chamber l2. An exhaust opening'15 is provided in the rear portion of the wall 35 and is surrounded by an outwardly projecting an-' nular lip '56. A cap 1'! surrounds the lip i5 and projects outwardly from the wall 35. Spaced openings 18 are provided in the wall of the cap 11 to communicate with the atmosphere. The

discharge valve I1 comprises a valve head or disc 19 shiftable in the cap 11 and adapted to seal inwardly against the outer edge of the lip 16. A spring bears inwardly against the disc 19 to urge it to its closed position on the lip 16 to close the discharge opening '15. Means is provided for regulating the action of the spring 89. A regulating screw El is threaded inwardly through the outer end of the cap 11 and has a flange part acting on the outer end of the spring Bil. The screw 8| is provided with a suitable handle or operating knob 82. When the patient exhales into the chamber I2 the valve 59 automatically closes as described above and the resultant increased pressure in the chamber l2 opens the disc 19 against the action of the spring 80 to allow the escape of the exhaled air and carbon dioxide from the chamber 12. Hooks or other suitable means 33 may be provided on the exterior of the body for receiving a strap to hold the device on the patients face.

Before employing the device to administer an anesthetic a suitable quantity of ether or other liquid anesthetic is provided in the reservoir H The level or quantity of the anesthetic in the reservoir may be readily .ascertained by means of the window 2i. Water or other liquid at a suitable high temperature is then filled into the space S of the heating jacket I3. In practice, it

has been found desirable to fill the space S with water at a temperature of about 212 immediately before administering the anesthetic. The valve l5 which may have been closed is opened by turning the knob 56 to provide for the discharge of liquid anesthetic into the mixing chamber H. The valve I5 may be accurately set or adjusted and its action may be observed through the inspection opening 26. The device is then placed on the face of the patient so that the chamber I2 is in direct communication with the oral and nasal cavities. Prior to the arrangement of the device on the patients face it may be necessary to adjust or turn the reservoir ID to a position where the anesthetic will not spill from the cap IS. The cushion member 35 engages the patients face to close the lower end of the chamber l2 so that the chamber is governed by the valves 59 and 1,9. At this point it may be remarked that pre-medication is not required when the device of this invention is employed to induce anesthesia and. no towels are required during any stages of the anesthetic. The exhaust valve H may be adjusted by means of the regulating screw 6! to control the discharge from the breathing chamber l2.

The liquid anesthetic dropping from the orifree 53 strikes the splash plate SI and is broken up to vaporize in the heated mixing chamber H. The hot water or heating medium in the space S maintains the mixing chamber at a temperature that insures the effective and complete vaporizing of the liquid anesthetic. In practice, it has been found that water placed in the space S at a temperature of about 212 immediately before the administering of the anesthetic maintains the proper temperature in the mixing chamber ii throughout the induction period of the anesthetic which ordinarily is from between 15 and 20 minutes duration. Following the induction period of the anesthetic the valve l5 may be regulated to supply the anesthetic to the mixing chamber H at a slower rate, and a lower temperature is desirable in the mixing chamber. As the temperature of the heating medium in the space S lowers, the anesthetic supplied to the chamber at a slower rate is completely vaporized by the air passing through the chamber. The insulation jacket I l and its contained thermal insulating material M aids in maintaining the desired temperature in the mixing chamber H and the chamber l2. The heating medium in the space S aids in maintaining the desired temperature in the chamber I2 as Well as in the mixing chamber H.

' When the patient inhales, a reduced pressure is created in the chamber l2 and the valve disc 59 opens to admit the warmed mixture of vaporized anesthetic and air from the mixing chamber H. This anesthetic mixture is, of course, breathed by the patient. When the patient exhales the valve 59 automatically closes and the increased pressure formed in the chamber I2 opens the valve disc 19 to permit the escape of controlled quantities of exhaled air and carbon dioxide. The spring 80 is preferably adjusted so that a certain desirable amount of exhaled air and carbon dioxide is trapped in the chamber l2 to be rebreathed during the following inhalation. The valves l and l i may be adjusted at any time during the administration of the anesthetic to provide for the desired anesthesiant mixture. Regulation of the valve 29 of course governs the admission of outside air to the warmed mixing chamber H.

The apparatus or device of this invention produces a warmed anesthesiant mixture in the chamber l2 and prevents the patient from inhaling raw or unvaporized anesthetic so that there are very short stages of induction and excitation. The device induces anesthesia with little or no nausea, headache, bronchial irritation or other ill effects. The blood pressure varies only slightly and the blood is highly aerated throughout the period of the anesthetic. Because of the controlled delivery of the anesthetic and its complete vaporization a minimum amount of anesthetic is required. The valve l1 operates to prevent the escape of any appreciable amount of anesthetic mixture from the breathing chamber l2 and as the reservoir ill is substantially closed there is very little loss of the anesthetic. The unit or assembly comprising the valve means 5 may be readily removed from the lower end of the mixingchamber ll to permit the interior of the device to be cleaned and sterilized. The plate 52 carries the valve 59, the absorbent element 60 and the splash plate 5! and is held in place by the bayonet slots 64% and pins 65 to be readily removed at will.

Having described only a typical form and application of my invention, I do not wish to be limited or restricted to the specific form and ap' plication herein set forth, but Wish to reserve to myself any modifications or variations that may appear to those skilled in the art or fall within the scope of the following claims.

Having described my invention, I claim:

1. In a portable anesthetic administering device the combination of, a mixing chamber, means supplying liquid anesthetic to the mixing chamber, means admitting air to the mixing chamber, a breathing chamber, a partition separating said chambers and having a valve controlled opening, means for preventing the anesthetic from falling directly through said opening, means surrounding the opening in the mixing chamber for trapping the liquid anesthetic to prevent the same from entering the opening in a liquid state, and a jacket around the mixing chamber for holding a heated liquid.

2. In a portable device for administering anesthetics, a body having a mixing chamber, a reservoir for holding a liquid anesthetic and having a filling opening, and means normally freely rotatably supporting the reservoir on the body where it delivers the anesthetic to the mixing chamber, the reservoir being turnable to positions where the liquid does not spill from the filling opening when the body is moved to various positions.

GARNET KING. 

